Bio-Based Inhibitors to Mitigate Internal Corrosion in Crude Oil Pipelines

According to a US DOT factsheet, about 12% of total pipeline accidents in the past 20 years are caused by internal pipeline corrosion. The internal corrosion in crude oil pipelines is caused by the contaminants and corrosives such as salt water, hydrogen sulfide, carbon dioxide, and bacteria. Film-forming corrosion inhibitors are commonly used in small quantities to mitigate internal corrosion in steel pipelines, which can be expensive, environmentally unfriendly, and partially effective under certain pipeline conditions. The present study aims at utilizing a novel bio-based corrosion inhibitor to mitigate internal corrosion in pipelines. Polyols are sugar alcohols primarily derived from corn starch, which are demonstrated in the past to inhibit chloride-induced corrosion in structural steels through physisorption. In this preliminary study, brine-in-corn oil emulsions containing polyol with weights ranging between 0% and 3% are prepared and dripped on uncoated ASTM A572 steel specimens to assess the corrosion inhibition efficiency of polyols. Significant corrosion protection is achieved by employing polyols in oil emulsions.